Add HOWTO for releasing Gitea (#5054)
Add HOWTO for releasing Gitea (#5054)

* Add HOWTO for releasing Gitea

Used instructions from: https://github.com/go-gitea/gitea/pull/2609#issuecomment-352159155

* Update CONTRIBUTING.md

sapk-fork/gitea,go-gitea/gitea,go-gitea/gitea,vdbt/gitea,lunny/gitea,typeless/gitea,lunny/gitea,lunny/gitea,typeless/gitea,Bwko/gitea,lafriks/gitea,go-gitea/gitea,sapk-fork/gitea,cez81/gitea,kubatyszko/gitea,typeless/gitea,typeless/gitea,Bwko/gitea,vCaesar/gitea,cez81/gitea,cez81/gitea,lafriks/gitea,lafriks/gitea,Bwko/gitea,sapk-fork/gitea,kubatyszko/gitea,kubatyszko/gitea,vCaesar/gitea,sapk-fork/gitea,vdbt/gitea